Ongoing Electroencephalographic Activity Associated with Cortical Arousal in Transgenic PDAPP Mice (hAPP V717F)

2018 ◽  
Vol 15 (3) ◽  
pp. 259-272 ◽  
Author(s):  
Claudio Del Percio ◽  
Wilhelmus Drinkenburg ◽  
Susanna Lopez ◽  
Cristina Limatola ◽  
Jesper F. Bastlund ◽  
...  
Keyword(s):  
Active State ◽  
Passive State ◽  
Large Animal ◽  
Cortical Arousal ◽  
Eeg Rhythms ◽  
Passive Condition ◽  
Disease Modifying Drugs ◽  
Theta Frequency ◽  
Neural Transmission ◽  
Electroencephalographic Activity

Background: It has been shown that theta (6-10 Hz) and delta (1-6 Hz) ongoing electroencephalographic (EEG) rhythms revealed variations in the cortical arousal in C57 Wild Type (WT) mice during cage exploration (active condition) compared to awake quiet behavior (passive condition; IMI PharmaCog project, www.pharmacog.eu). Objective: The objective was to test if these EEG rhythms might be abnormal in old PDAPP mice modeling Alzheimer's disease (AD) with a hAPP Indiana V717F mutation (They show abnormal neural transmission, cognitive deficits, and brain accumulation of Aβ1-42). Methods: Ongoing EEG rhythms were recorded by a frontoparietal bipolar channel in 15 PDAPP and 23 WT C57 male mice (mean age of 22.8 months ±0.4 and 0.3 standard error, respectively). EEG absolute power (density) was calculated. Frequency and amplitude of individual delta and theta frequency (IDF and ITF) peaks were considered during passive and active states in the wakefulness. Results: Compared with the WT group, the PDAPP group showed higher frequency of the IDF during the passive condition and lower frequency of the ITF during the active state. Furthermore, the WT but not PDAPP group showed significant changes in the frontoparietal EEG power (IDF, ITF) during active over passive state. Conclusion: PDAPP mice were characterized by less changes in the brain arousal during an active state as revealed by frontoparietal EEG rhythms. Future studies will have to cross-validate the present results on large animal groups, clarify the neurophysiological underpinning of the effect, and test if the disease modifying drugs against AD amyloidosis normalize those candiate EEG biomarkers in PDAPP mice

scholarly journals Ongoing Electroencephalographic Rhythms Related to Exploratory Movements in Transgenic TASTPM Mice

2020 ◽  
Vol 78 (1) ◽  
pp. 291-308 ◽  
Author(s):  
Claudio Del Percio ◽  
Wilhelmus Drinkenburg ◽  
Susanna Lopez ◽  
Maria Teresa Pascarelli ◽  
Roberta Lizio ◽  
...  
Keyword(s):  
Cognitive Deficits ◽  
Wild Type ◽  
Eeg Rhythms ◽  
Double Mutation ◽  
Passive Condition ◽  
Theta Frequency ◽  
Pros And Cons ◽  
Active Condition ◽  
Eeg Power ◽  
Exploratory Movements

Background: The European PharmaCog study (http://www.pharmacog.org) has reported a reduction in delta (1–6 Hz) electroencephalographic (EEG) power (density) during cage exploration (active condition) compared with quiet wakefulness (passive condition) in PDAPP mice (hAPP Indiana V717F mutation) modeling Alzheimer’s disease (AD) amyloidosis and cognitive deficits. Objective: Here, we tested the reproducibility of that evidence in TASTPM mice (double mutation in APP KM670/671NL and PSEN1 M146V), which develop brain amyloidosis and cognitive deficits over aging. The reliability of that evidence was examined in four research centers of the PharmaCog study. Methods: Ongoing EEG rhythms were recorded from a frontoparietal bipolar channel in 29 TASTPM and 58 matched “wild type” C57 mice (range of age: 12–24 months). Normalized EEG power was calculated. Frequency and amplitude of individual delta and theta frequency (IDF and ITF) peaks were considered during the passive and active conditions. Results: Compared with the “wild type” group, the TASTPM group showed a significantly lower reduction in IDF power during the active over the passive condition (p < 0.05). This effect was observed in 3 out of 4 EEG recording units. Conclusion: TASTPM mice were characterized by “poor reactivity” of delta EEG rhythms during the cage exploration in line with previous evidence in PDAPP mice. The reliability of that result across the centers was moderate, thus unveiling pros and cons of multicenter preclinical EEG trials in TASTPM mice useful for planning future studies.

scholarly journals Interval between two sequential arrays determines their storage state in visual working memory

2020 ◽  
Author(s):  
Ziyuan Li ◽  
Jiafeng Zhang ◽  
Tengfei Liang ◽  
Chaoxiong Ye ◽  
Qiang Liu
Keyword(s):  
Working Memory ◽  
Visual Working Memory ◽  
Visual Information ◽  
Active State ◽  
Passive State ◽  
Dynamic Nature ◽  
Retention Period ◽  
Memory Representations ◽  
Interval Condition ◽  
First Time

AbstractThe visual information can be stored as either “active” representations in the active state or “activity-silent” representations in the passive state during the retention period in visual working memory (VWM). Catering to the dynamic nature of visual world, we explored how the temporally dynamic visual input was stored in VWM. In the current study, the memory arrays were presented sequentially, and the contralateral delay activity (CDA), an electrophysiological measure, was used to identify whether the memory representations were transferred into the passive state. Participants were instructed to encode two sequential arrays and retrieve them respectively, with two conditions of interval across the two arrays: 400ms and 800ms. These results provided strong evidence for the state-separated storage of two sequential arrays in different neural states if the interval between them was long enough, and the concurrent storage of them in the active state if the interval was relatively short. This conclusion was valid only when the participants encountered the task for the first time. Once participants have formed their mindset, they would apply the same storage mode to the subsequently extended or shortened interval condition.

scholarly journals II. The passive state of iron and steel. Part III

1891 ◽  
Vol 49 (296-301) ◽  
pp. 481-488
Keyword(s):  
Nitric Acid ◽  
Chemical Composition ◽  
Steel Part ◽  
Physical Structure ◽  
Passive State ◽  
Passive Condition ◽  
Iron And Steel ◽  
Wrought Iron

The author is not aware that any previous experiments have hitherto been made showing the relative passivity of the various kinds of steel compared with wrought iron, or the influence of the chemical composition and physical structure of such metals on their passive condition in nitric acid.

scholarly journals II. The passive state of iron and steel. Part II

1891 ◽  
Vol 49 (296-301) ◽  
pp. 120-126
Keyword(s):  
Nitric Acid ◽  
Royal Society ◽  
Steel Part ◽  
Passive State ◽  
Effect Of Temperature ◽  
Passive Condition ◽  
Iron And Steel ◽  
Varied Concentration

In Part I of this research (‘Roy. Soc. Proc.,’ vol. 48, p. 116), the author showed the influence of magnetisation on the passive state of iron and steel, and he has now the pleasure of communicating to the Royal Society the results of a further study of certain temperature and other conditions affecting the passivity of these metals in concentrated nitric acid. The experiments of Series III, in this paper, relate to the effect of temperature, and the observations of Series IV refer to the influence exerted by nitric acids, of varied concentration, on the passive condition of iron and steel.

scholarly journals Comportamento de armaduras galvanizadas em diferentes alcalinidades

2018 ◽  
Vol 1 (42) ◽  
pp. 128
Author(s):  
Gibson Rocha Meira ◽  
Karolina Ferreira ◽  
Taissa Guedes Cândido ◽  
Mariane Carvalho
Keyword(s):  
Corrosion Potential ◽  
The Other ◽  
Passive State ◽  
Alkaline Solutions ◽  
Corrosion Activity ◽  
Passive Condition ◽  
Other Hand

<p>Taking into account the few studies carried out about hot-dipped galvanized reinforcements, this work aimed to study the behaviour of these reinforcements in different alkalinity media and subjected to subsequent carbonation. For this purpose, galvanized and carbon reinforcements were immersed in alkaline solutions and electrochemically monitored to evaluate their behaviour. Results show that galvanized reinforcements present good performance in carbonated media and also in media with pH lower than 13.3, which presented corrosion potential under levels that indicate a passive state of reinforcementsregarding corrosion. On the other hand, carbon reinforcements present corrosion activity in carbonated media and passive condition in medias with pHs over 12.5.</p>

Some Mechanical Considerations in the Selection and Testing of Papillary Muscles

1980 ◽  
Vol 102 (1) ◽  
pp. 62-66 ◽  
Author(s):  
J. G. Pinto
Keyword(s):  
Mechanical Testing ◽  
Mechanical Response ◽  
Testing Machine ◽  
Active State ◽  
Minimum Size ◽  
Passive State ◽  
Papillary Muscles ◽  
Segment Size ◽  
Deformational Behavior ◽  
Shape And Size

Measurements of segmental deformation made on papillary muscles obtained from cat, rabbit, dog and pig hearts suggest that the deformational behavior in these specimens is appreciably nonuniform both in the resting (passive) state and in the stimulated (active) state. In view of this, in the mechanical testing of papillary muscles, it is necessary to establish a minimum size of segment “sufficiently” far from the disturbing influence of end fixtures generally used to hold the specimen in the testing machine. The segment size should be large enough to average out the nonuniform aspects of deformation. Thus, the shape and size of the specimen dictated by the nonuniformities in the mechanical response, the thinness of the specimen dictated by the viability considerations and aspects of the testing machines and method dictated by the visco-elastic features of the specimen should be given due consideraton in the selection and testing of papillary muscles.

scholarly journals The photo-electric behaviour of iron in the active and passive state

1913 ◽  
Vol 88 (600) ◽  
pp. 70-74 ◽  
Keyword(s):  
Nitric Acid ◽  
Ultra Violet ◽  
Electric Activity ◽  
Metal Plate ◽  
Passive State ◽  
Passive Condition ◽  
General Acceptance ◽  
Metal Form ◽  
Air Condenser ◽  
Polished Metal

The discoveries of Hertz and of Hallwachs showed that a polished metal plate exposed to ultra-violet light readily loses a negative electric charge, but retains a positive charge. If an electric Held is applied by making the metal form one plate of an air condenser, whose second plate is charged positively by a battery, the saturation current obtained may be regarded as a measure of the photo-electric activity of the metal. It has been known for more than a century that ordinary iron, which is acted on energetically by dilute nitric acid, can be made to assume a passive condition by immersion in strong nitric acid. The same condition can be produced by other powerful oxidising agents, or by using iron as the positive electrode in an electrolyte containing oxygen. The nature of the change that takes place when iron passes from the active to the passive state has given rise to much discussion, but none of the explanations suggested has yet met with general acceptance.

scholarly journals On-Going Frontal Alpha Rhythms Are Dominant in Passive State and Desynchronize in Active State in Adult Gray Mouse Lemurs

PLoS ONE ◽  
2015 ◽  
Vol 10 (11) ◽  
pp. e0143719 ◽  
Author(s):  
Francesco Infarinato ◽  
Anisur Rahman ◽  
Claudio Del Percio ◽  
Yves Lamberty ◽  
Regis Bordet ◽  
...  
Keyword(s):  
Active State ◽  
Passive State ◽  
Mouse Lemurs

scholarly journals Energy Efficient Beacon Scheduling in WSN

2019 ◽  
Vol 9 (2) ◽  
pp. 2036-2039
Keyword(s):  
Energy Consumption ◽  
Wireless Sensor Network ◽  
Sensor Network ◽  
Mac Protocol ◽  
Active State ◽  
Wireless Sensor ◽  
Passive State ◽  
Slave Node ◽  
Sleep State ◽  
Beacon Frame

In wireless sensor network the main source of energy consumption is Idle listening. Keeping energy consumption in mind the wireless sensor network should quickly sensing data. The communication between the nodes is only possible when both nodes are in active state. In this paper, we have implemented a modified beacon scheduling in the recipient MAC protocol. the data will be transmitted to the node in the active state thus effectively saving the energy consumption in the idle state. For transmission of data, synchronization of all nodes is important. Each node has its defined time slot to avoid collision of data. The receiver node sends a beacon frame request to the slave node in active state in response to it the slave node sends data frame if any to the node. The communication takes place only in the active state thus saving the energy in passive state (sleep state). The system is simulated in visual basic software and the graphs are plotted accordingly. It also shows the active and sleepy state of the network.

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